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 Jan 21 comment Number of non-identity, self-inverse elements in an Abelian group of order 10 I'm not a mathematician and I fail to see how this answers the question. Oct 15 comment Computing $\lim_{x→\infty}\ln(3x ^2 − 4x + 2) − \ln(5x ^2 + 19x − 1)$ The "swapping" of $\ln$ and $\lim$ is only allowed if the resulting limit converges, not just because $\ln$ is continuous! Jul 29 comment When I was teaching absolute function properties, I suddenly made this question … @Khosrotash It makes people that didn't see this immediately, feel dumber than the rest. May 27 comment Is there such a thing as complex rational numbers and does it have the same properties as the usual complex numbers as extension of the real numbers? @AlexR Could is be used to say, define useful quantum physics, and would the limitations of the field $\mathbb{Q}(\mathrm{i})$ be in any way meaningful when interpreted physically? Oct 17 comment Limit of a 0/0 function A hard requirement of the usability of l'Hôpital's rule is that the resulting "right-hand-size" is exists. But I guess that's what Hans is saying in more fancy terms? May 12 comment How is the multiplicity of a pole defined when square roots are involved? Yes, of course, never cross the branch cut, but I'll need to calculate a limiting small circle integral around that point from one side of the cut to the other if I'm to avoid them, My question is more about that than the real residue which is defined differently for these points if it even exists. Dec 9 comment Math question please ? Complex numbers? you need a $\pm$ instead of a $+$ in your second-to-last step. I can't edit such a small typo, hence the comment. Dec 9 comment Solving a geometric algebra equation When you put it like that, it seems so simple... Thanks. Dec 9 comment Solving a geometric algebra equation @GiuseppeNegro thanks for the additional reference. I'll be sure to check it out! Dec 8 comment Solving a geometric algebra equation a,b, and c are vectors, $\alpha$ is a scalar. Juxtaposition is geometric product, dot is inner product. Dec 3 comment How to simplify $\frac{4 + 2\sqrt6}{\sqrt{5 + 2\sqrt{6}}}$? Isn't this how you show 5 equals 4? Aug 16 comment Is addition more fundamental than subtraction? @Lee: and a metric is positive by definition. Aug 15 comment Is addition more fundamental than subtraction? @user1729 in my defense, I touched that aspect already in this comment Aug 15 comment Is addition more fundamental than subtraction? A subtraction like this does not conform to the natural definition subtraction has. A metric is positive definite, subtraction is not. Aug 14 comment Is addition more fundamental than subtraction? @AustinMohr: I'll keep that in mind. Sorry about that. Aug 14 comment Is addition more fundamental than subtraction? @Drise: completely equivalent after the isomorphic transformation. So in Math speak: completely equivalent. Aug 14 comment Is addition more fundamental than subtraction? Reversing the two concepts just leaves you with two isomorphic concepts that does not answer the question. Jul 31 comment What's the meaning of the unit bivector i? @draks that is not geometric algebra. That's Dirac algebra which only makes sense in Dirac theory. Geometric algebra promises (I'm still learning) to be applicable/useful everywhere, not just in the case of $\gamma$s. And an index $i$ is nothing evil. Jul 31 comment What's the meaning of the unit bivector i? @celtschk OK. But Hestenes maintains quaternions are just an aspect/transformation/... of the more general geometric algebra (at least in sofar they are used in Physics). I can't deduce any geometric meaning from quaternions either, so although insightful, it doesn't help me much (probably why you made it a comment anyways ;-)). Jul 31 comment What's the meaning of the unit bivector i? OK. This is part of the meaning I get. The bivector as an operator is a rotor. But the bivector as basis element of the algebra should have a meaning on its own. Is my plane interpretation correct?